I. Field of the Invention
This invention relates generally to safety apparatus for preventing fires caused by the entrapment of heat from recessed ceiling light fixtures, and more specifically to a kit which may be utilized by construction or insulation contractors for maintaining a safe spacing of thermal insulation from the recessed light fixture such that heat dissipating air circulation about the fixture can be maintained.
II. Description of the Prior Art
In residential and commercial building structures it is common practice to insulate the ceiling by blowing cellulose material into the attic space so that it covers the ceiling of the living space to a predetermined thickness. Alternatively, fiberglass bats are installed between the ceiling joists to inhibit the flow of heat from the living space through the ceiling to the attic space. It is also common practice to utilize recessed lighting fixtures in the living space which include a portion which extends through the ceiling into the attic space. If the thermal insulation blanket is permitted to encroach upon the recessed light fixture, there is the potential for heat entrapment and excessive heat build up within the recessed lighting fixture which could result in damage to the wiring or to the surrounding combustible materials used in the building construction.
Because of the potential for fire, Paragraph 410-66 of the National Electric Code 1978 provides:
"Clearance for flush and recessed fixtures--Recessed portions of enclosures, other than at points of support, shall be spaced at least 1/2" from combustible material. Thermal insulation shall not be installed within 3" of the recessed fixture enclosure, wiring compartment or ballast, and shall not be so installed above the fixture so as to entrap heat and prevent the free circulation of air unless the fixture is otherwise approved for the purpose."
In order to comply with this code requirement, builders have used a number of expedients, none of which offers the versitility of the present invention. For example, during construction of the building, it is common practice to build a wooden teepee-type structure over the fixture with two sides thereof being open. While this arrangement is generally suitable for use when insulation bats are employed, it does not solve the problem when blown-in insulation is utilized. When loose cellulose type blown insulation is employed, it too can build up within the teepee structure and blanket the recessed light fixture. Then too, the time which it takes to fabricate the structure at the site out of plywood and install it over the recessed light fixture is quite time consuming and therefore costly.
I am also aware of a product sold under the trademark INSUL-CAN by the Insul Can Company of Oklahoma City, Okla. which is designed to solve the problem of maintaining a minimum safe clearance between the thermal insulation and a recessed light fixture in the attic space of a building. This product comprises a trapezoidal container fabricated from sheet metal and which has an open bottom so that it may be placed over the extension of the light fixture which is in the attic space. However, it is found that this device does not meet the aforementioned National Electric Code in that it does not prevent the free circulation of air about the fixture and merely serves to enlarge the volume of air whose temperature is increased by the presence of the recessed light fixture therein.